Brake-beam.



PA TE NTED JUNE 12, 1906.

WQSTEVENSON.

BRAKE BEAM.

APPLICATION FILED MAR-12,1906:

, witn ess es UNITED sTATns PATENT BRAKE-BEAM Specification of Letters Patent.

Patented J .a 1

, recs.

Application filed March 12.1906. Serial No. 305,558.

To all whom, it may-concern:

Be itknown that I, WILLIAM STEVEXSON,

. a citizen of the United States, and a resident of Chicago, Cook county, Illinois, have invented a certain new, useful, and Improved BrakeBeam, of which the following is a full, clear, and exact specification, such as -will enable others skilled in the art to which it pertains to make and use the same.

My invention relates to improvements in brake-beams, and has special reference to improvements inbrake-beams of that class which are known as single-member beams, such a brake-beam having as its principal member a rolled flanged beam of structural shape, usually an I-beam.

The object of my invention is to provide a brake-beam which shall be of minimum weight and of maximum strength.

Anotherobject of the invention is to provide a brake-beam at less cost than any other brake-beams of its class.

. dle of the beam.

My invention also consists in particular forms and constructions and in combinations of parts, all as hereinafter described, and

pointed out in the appended claims.

My'invention will be more readily understood by reference to the accompanying drawings, forming part of this specification,

V and in which-- linear of Fig. 1.

Figure l is a top view of a brake-beam embodying my invention. Fig. 2 is a top view of the main element or member of my improved brake-beam, slightly modified. Fig. 3 is an enlarged cross-section thereof on the cation of the structure in which a single bolt is employed for securing the fulcrum-pieces.

Fig. 5 is a view showing the beam with a modified middle cross-section. Fig. 6 is an enlargedcross-section or end view of the beam, standing also for thecross-section of the original beambefore it is spread, as hereinafter described.

' The purpose of this invention is toimprove I what is known as the single-beam type of brake beam. Brake beams of this class which are now on the market are made from five-inch and from six-inch Idoeams of stand- Fig. 4 illustrates a modifi-- ard cross-sections; It is well known that the five-inch brake-beams whichare now in use do not comply wth the requirements of the Master Car-Builders Association, forasmuch as they are deficient in strength. It is for this reason that the six-inch beam was resorted to. The objection to the six-inch beam is thatits uddthis too great to admit it in the space which isallowed in the car-truck. This is also true of the five-inch beam, and out of this fact has grown a custom of compressing the ends of both five and six inch beams to a dimension of about four inches. The ordinary truck will not accommodate a larger beam when the brake-heads and brakeshoes are applied thereto. The manifest and well-known advantages of a single beam, and particularly the low cost of such brakebeams, has led to the use of large numbers thereof notwithstanding the fact that they are comparatively inefficient and unreliable. The beams which are compressed or reduced in height at the endsvsuffer from this distortion, being thereby further weakened, and it is also well known that the process of com pressing the ends is slow and expensive. Fur-- thermore, thecompressed end ofsuch a beam offers a poor seat for the brakeshoe head, which must needs be attached thereto.

The special object of my invention is to provide a brake-beam which shall be free from the faults, weaknesses, and other objectionable features of the single-beam devices in present use andto provide a beam which shall be of even less weight than the ordinary beam and yet stronger and which shall have ends that are admirably fitted to receive the brake-shoe heads. I accomplish these ends by making and employing a 5 rolled flanged beam of a new cross-section, the characteristic of which is that its flange width is equal to or is greater than the beams height. When the beam is in use, its web occupies a horizontal plane; but in describing the same I shall employ ordinary terms, referring to the distance between the edges of the flanges as the width of the beams and terming the distance across the web as the neight of the beam.

My invention may be carried out with a rolled flanged beam of channel shape in crosssection; but I much prefer a 'beam of T shape in crosssection. In either case the width of the beam equals or exceeds the height of the 1 1o beam.

Practically speaking, the height of the beam is determined bythe space that is available in the truck to which the brake beam is to be applied, taken in connection with the pull or load which is to be imposed upon t bet-"n, and from the foregoing it will be View that the width of the beam is determined by its height. The wide flanges of the beam are amply suflicient to Withstand all transverse stresses,'bu t beingof small height, usually not exceeding four inches, would not be strong enough to sustain the direct pull of the brake mechanism on the beam. To overcome this difficulty and to secure the necessary strength at the center of the beam, I separate or force apart the two flanges until they occupy the requisite relation to the neutral axis of .the beam. The flanges are then braced by a strut, the beam taking the form of a fish-belly beam of theoretical shape proportioned to the same loads. The ends of the beam are not distorted in any way, and therefore provide the best possible seats for the brake-shoe heads.

Referring now to the drawings, and particularly to Fig. -6, it Will be seen that I employ a beam whose web 2 is of no greater, and usually of less, width than the flanges 33. Fig. 6 represents the cross-section f the original beam and also represents tln "osssections of the ends of the completed brakebeam. The middle of the beam is of greater height, the flanges 3 3being separated at that point, as shown by the other figures of the drawings. For illustration, in cases where the ends of the beam are four inches in height I make the middle of the beam at least six inches in height. When the separated flanges are joined by a strut, such beam becomes quite as strong, in fact stronger, than the usual six-inch Ibeam. It weighs much less, costs less, and is stronger than the usual beam, and herein lies the special advantage of my invention. H

By applying sufficient force the middle or central portion of the web of the beam may be distended (see Fig. 1) without rupturing the web by thinning the same, as shown at 2 in Fig. 5. The pulling or spreading ofthe flanges may be facilitated by splitting the web of the beam, as shown in Fig. 2, and this is the preferred way of making the member. I prefer that the compressionfla-nge'i. e the flange opposite the brake-head s---shall be straight, as shown in. the drawings; but it is obvious that both flanges of my beam may be distended, if desired, and it is also obvious that the degree of distension---in other words, the distance between the flanges at the center of the bCiIllP-IlQtQlniiDQS the load-carryin strength thereof.

1 may provide my beam with a strut or struts independent of the fulcrum-piece; but as the fulcrum-piece requires a fastening upon the beam I prefer to make the struts and the fulcrum-nieceinte ral. Thus the ang'ularlvpositioned fulcrum piece or j-aw 6 is preferably formed in two parts, the member 6 of which embraces the flanges and the tveb of the beam. 'These portions are secured together and to the beam by one or more rivets 6 and constitute an effective strut. If desired, a single rivet 6 may be used, as shown in Fig. 4. Such construction avoids the piercing of theweb portions; but in most cases I provide each of the web parts 2' with a rivet-hole to receive the rivets 6. The strut serves to hold the flanges 3 3 in fixed position at the'center, and at the ends the flanges are joined by the solid portions of the web 2. The brake-heads 5 may be of any desired pattern or form and are made to closely fit the ends of the tension-flange of the beam and also the web of the beam. They are secured upon the beam by means of rivets or bolts 5,. In manufacturing these beams I prefer that one flange shall be held in a stationary die and that the other shall be grasped in a movable die or clamp,

the latter being drawn or pulled away from the stationary dieuntil the beam is given the necessary web height. As stated, the operation is simplified by previously splitting the web, as indicated in Fig. 2. The torturing or rupturing of the inetalat the ends of the beams may be wholly averted by subjecting the'beam to endwise pressure during the op-' eration of the dies. The manner of treating a channel-beam is'the'same as described in connection with an I-beam.

As various modifications of my brakebeam as herein shown and described will readily suggest themselves to others, I do not confine my invention to these specific constructions. i p

Having thus described my invention, I claim as new and desire to secure by Letters Patent 1. A brake-beam of the single-beam type comprising a single, rolled, flanged beam of a width at least equaling its height and having its flanges forced apart at the middle, in combination with a suitable strut, fulcrum-piece and heads, substantially as described.

2. A brake-beam of the single-beam type comprisin a single, rolled, flanged beam of ha flanges whose width 5 heads,'snbstantially as described.

5. A brake-beam comprising a. single, rolled, I-beam, having its web s lit and its flanges distended at the middle, t e width of said flanges'being at least equal to the height of thweb at the ends of the beam, in combination with a suitable strut, a fulcrum'and brake-heads, substantially as described.

6. A brake-beam comprising a single, I rolled, 145631111, of a Width at least equaling its hei ht and having its Web distended at the mi dle, whereby the flanges are abnormally separated at that point, in combination with a fulcrum-piece, corrected portions forming a strut between the flanges of the beam and brake-heads attached to the ends of said beam, substantiall as described.

In testimony whereof have hereuntos et my hand, this 8th day of March, 1906, in the presence of two subscribing witnesses.

7 WILLIAM STEVENSON.

Witnesses-z M. SIMON, H. S. AUSTIN. 

